Surface Structure and Cells Adhesion on Doped Polyethylene

Abstract:

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The properties of polyethylene doped with Ca2+ salt of oxidized cellulose was studied by
different techniques. FTIR spectroscopy was used for the determination of crystalline phase in
polymer film, surface wettability was determined by standard goniometry and surface morphology
was examined by SEM microscopy. Adhesion of mouse 3T3 fibroblasts on the doped polymer was
studied in vitro. It was found that the polyethylene doped with the cellulose derivative can be
sterilized in boiling water. The number and homogeneity of adhering cells were shown to depend on
the surface wettability and morphology.

Abstract: This work involved a study of polymer-fiber composites as biodegradable packaging made from recycled polyethylene (r-PE) and chemical-treated cotton fabric waste micro fibers. A compatibilizer, polyethylene-graft-maleic anhydride (PE-g-MA), was used to improve properties of the composites. Factors affecting composite properties were investigated including % PE-g-MA loading, and % fiber loading. The fiber composites were prepared by melt-blending technique. The materials were first mixed by a twin-screw extruder and shaped into samples by an extrusion blow molding machine. The samples were then characterized for mechanical, and morphological properties. It was found that properties of the composites were improved by adding the compatibilizer. Optimum properties of the composites were found at 10% (wt%) PE-g-MA loading. It was also revealed that tensile strength and modulus was found to increase as the % fiber loading was increased. SEM micrographs confirmed that interfacial bonding between the cellulose fibers and the r-PE matrix was enhanced as fewer voids at the interfaces were revealed by adding the PE-g-MA compatibilizer to the composites. Film formation occurred on all composites even if the polymer itself was inert biodegradation. The microbial colonization affected mainly of surface properties r-PE composites while changes were monitored also in the bulk properties of cellulose microfiber.

Abstract: Collagen/cellulose films were made by the blend solutions of collagen, cellulose in this paper. To begin with, collagen and cellulose was dissolved in 1-allyl-3-methylimidazolium chloride ([Amim]Cl）. The structure of the blend films was characterized by FTIR and XRD. The effects of weight ratio between the two polymers on light transmittance, tensile strength, elongation at break and water absorption of the film were studied. The results showed that there were strong interactions and good compatibility between collagen and cellulose in the film and the polymers have strongest interactions at the mixing ratio of 5:5. The blend films possess better properties such as mechanical and water absorption properties than those made of single polymer.

Abstract: A novel composites material consisting of calcium silicate deposited in bacterial cellulose membrane was synthesized by immersing BC membrane in the calcium and silicate solutions by turns with different cycle times and characterized. The results indicated that the CaSiO3 particles were homogeneously dispersed on the surface of nanofibers with the effect of BC template when two cycles of soaking proceed, during which the fabrication of most CaSiO3 particles took place. The FT-IR reveals the strong interaction between the two parts of the BC/CaSiO3 composite. The XRD pattern demonstrated a crystal structure disruption of the cellulose aroused by CaSiO3 particle. BC/ CaSiO3 is considered to have a potential application in bone tissue field.

Abstract: The fibers were converted to nano-scale cellulose fibers by chemical and mechanical treatment in this paper. FT-IR spectroscopic analysis demonstrated that hemicelluloses and lignin were removed during the chemical process. After that, ultralsonication method was carried out to refine cellulose fibers to cellulose nanofibers (CNFs). The filtered CNFs film was freeze-dried. Scanning electron microscopy (SEM) images reflected a very high aspect ratio of single cellulose nanofiber was over 1000. The nanocomposites were fabricated to be transparent attributed to the good morphology of the nanocellulose. From the SEM images of fracture surface of nanocomposites, excellent distribution had been found in the nanocomposites. Elastic modulus of the nanocomposite film was determined through tensile test, which was typically higher than pure acrylic resin. Therefore, the obtained transparent nanocomposites with superior flexibility have the potential to be used as the base substrate for organic light-emitting diode display (OLED).

Abstract: Grafting vinyl monomers onto natural cellulose become a preferred method to derive water retaining agent because it afforded unique environmental and commercial advantages. In current work, a series of water retaining agent were prepared by radical solution polymerization of cellulose, partially neutralized acrylic acid and acrylamide using grafted agents as an initiator and N, N-methylenebisacryl- amide as a crosslinker. Fourier transform infrared spectroscopy spectra proved that acrylic acid and acrylamide were grafted onto cellulose backbone and N, N-methylenebisacryl- amide participated in polymerization. The effects of reaction conditions of reaction temperature and initiator amount to water retaining agent were studied using water absorbencies as evaluation standard, the optimum preparation technology was decided.